This has to be the very earliest Gene Autry Comic which is based on the Gene Autry movie called "Mexicali Rose" released in 1939.
The Comic is called Movie Comic # 03 issued June 1939. Only the Gene Autry story is in the comic.
Look for the file in .cbz format.
For a Free Download of Comic Books based on Movie and TV Western Cowboy Stars such as: Buck Jones, Cisco Kid, Durango Kid, Gene Autry, Hopalong Cassidy, John Wayne, Johnny Mack Brown, Lash LaRue, The Lone Ranger, Rocky Lane, Roy Rogers, Tim Holt, Zane Grey, Zorro, TV Westerns, Movie Westerns and many more, go to this web site: